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Mu XC, Tran TA, Ross JS, Carlson JA. Topoisomerase II-alpha expression in melanocytic nevi and malignant melanoma. J Cutan Pathol 2000; 27:242-8. [PMID: 10847549 DOI: 10.1034/j.1600-0560.2000.027005242.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Malignant melanoma (MM) is considered to be a chemotherapy-refractory tumor. New anti-cancer drugs (e.g. etoposide) that target DNA topoisomerases (e.g. topoisomerase II-alpha (topo IIalpha)) show activity against a wide variety of solid tumors. In this study, we investigated the frequency and rate of labeling for topo IIalpha in 163 MMs (primary and metastatic) and 67 melanocytic nevi to determine whether topo IIalpha expression is elevated in MM. Primary MM exhibited significantly more frequent topo IIalpha expression compared to benign nevi (86% vs. 56%, p=0.0001). The rate of topo IIalpha labeling in dysplastic melanocytic nevi, radial growth phase MM, vertical growth phase MM and metastatic MM revealed significant differences amongst groups and a positive covariance with advancing stage (means: 0.3, 0.5, 5, and 8 '+' cells/hpf, respectively; r=0.3, all p < or = 0.02). Topo IIalpha labeling significantly correlated with increasing mitotic activity, depth of invasion and Clark's level, diminishing tumor infiltrating lymphocytes, and poor outcome (all p < or = 0.01) in primary MM. For metastatic MM, a minority (30%) exhibited marked elevation of topo IIalpha expression. These findings indicate topo IIalpha as a potential therapeutic target and marker for MM. Immunohistochemical analysis of disseminated MM may allow for correlation with clinical response and enable selection of candidates sensitive for specific chemotherapy.
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Tran TA, Ross JS, Sheehan CE, Carlson JA. Comparison of oncostatin M expression in keratoacanthoma and squamous cell carcinoma. Mod Pathol 2000; 13:427-32. [PMID: 10786810 DOI: 10.1038/modpathol.3880073] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Oncostatin M (OSM) is a 28-kDa glycoprotein, produced by stimulated macrophages and T lymphocytes, that inhibits the proliferation and induces differentiation of a number of different cell lines derived from solid tumors. To determine whether keratoacanthoma (KA) is unique or a variant of squamous cell carcinoma (SCC), we compared the immunohistochemical expression of OSM in the tumor cells and peri- and intratumoral macrophages of 21 mature KAs, 7 regressing KAs, and 27 SCCs. An inverse correlation was identified between OSM tumor labeling and the density of OSM-labeled tumor-associated macrophages for KAs (r = -.4; P = .09). OSM tumor expression was significantly more frequent and more intense in KAs than in SCCs (95% versus 63%; P < .01). In contrast, the density of OSM-labeled macrophages was significantly higher in SCCs compared with mature KAs (7/3 high power fields versus 4/3 high power fields; P = .02). These OSM-positive macrophages were predominantly located at the advancing, infiltrative margins of both neoplasms. Regressing KAs demonstrated a decreased level of OSM tumor expression compared with mature KAs (53% versus 95%; P = .001), but there was no difference in density of OSM-labeled macrophages. Both the above differences and the overlapping patterns of OSM expression suggest that KAs are a variant of SCC where OSM, possibly as an autocrine factor, may mediate KA's overwhelming but not absolute tendency to involute.
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Brinker DA, Ross JS, Tran TA, Jones DM, Epstein JI. Can ploidy of prostate carcinoma diagnosed on needle biopsy predict radical prostatectomy stage and grade? J Urol 1999; 162:2036-9. [PMID: 10569563 DOI: 10.1016/s0022-5347(05)68094-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
PURPOSE Deoxyribonucleic acid ploidy correlates with the biological behavior of prostate carcinoma. However, the usefulness of ploidy on needle biopsies that show prostate cancer has not been established to our knowledge. MATERIALS AND METHODS We retrospectively determined ploidy on needle biopsies of 159 men with prostate carcinoma treated surgically at Johns Hopkins Hospital. Ploidy was determined by image analysis of Feulgen stained slides. Needle ploidy and Gleason score were compared as prognostic tools in the prediction of grade and stage of subsequent prostatectomy. RESULTS Of the 159 cases 98 (62%) were diploid, 16 (10%) tetraploid and 45 (28%) aneuploid. Of the diploid, tetraploid and aneuploid tumors 69, 50 and 44%, respectively, proved to be organ confined. Tetraploid and aneuploid tumors were grouped for the remaining analysis. Needle ploidy correlated significantly with pathological stage (p = 0.003). However, needle Gleason score correlated even more strongly (p <0.001), and on multivariate analysis ploidy was not further predictive of pathological stage once Gleason score was considered. Needle ploidy and Gleason score were predictive of prostatectomy Gleason score (6 or less versus 7 or greater), and on multivariate analysis ploidy was an independently significant predictor of this parameter (p = 0.04). In 13 cases (8%) there was an important grading discrepancy, in which needle ploidy would have accurately predicted prostatectomy grade. However, in 33 cases (21%) needle and prostatectomy Gleason scores were congruent, and needle ploidy did not accurately predict prostatectomy Gleason score. CONCLUSIONS With accurate needle Gleason grading, ploidy is not helpful in predicting prostatectomy findings. However, ploidy correlates with prostatectomy stage and grade, and may be useful if accurate Gleason grading is a concern.
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Tran TA, Ross JS, Boehm JR, Carlson JA. Comparison of mitotic cyclins and cyclin-dependent kinase expression in keratoacanthoma and squamous cell carcinoma. J Cutan Pathol 1999; 26:391-7. [PMID: 10551411 DOI: 10.1111/j.1600-0560.1999.tb01863.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Disruption of the cell-cycle regulation through over-expression or mutation of cyclins and cyclin-dependent kinases has been implicated in carcinogenesis. In order to determine whether keratoacanthoma (KA) is unique or a variant of squamous cell carcinoma (SCC) and whether expression of mitosis-related antigens are associated with KAs' tendency to regress, we compared the immunohistochemical expression of mitotic cyclins (cyclins A and B) and their cyclin-dependent kinase p34(cdc2) in 21 KAs, 8 regressing KAs, and 28 conventional squamous cell carcinomas. KAs showed both overlap and significant differences in expression of these mitosis-related antigens compared to SCCs. Basal and parabasal pattern of expression of cyclins A and B significantly predominated in KAs in contrast to SCCs which exhibited diffuse pattern (cyclin A 86%/cyclin B 64% vs. 25%/36%, p < 0.01). However, no differences in the highest mean level of expression in 'hot spot' loci of cyclins A and B were identified comparing KAs to SCCs (19%/12% vs. 25%/13%, p > 0.05). For the cyclin-dependent kinase p34(cdc2), no differences in pattern, distribution or mean levels of expression were found. For cyclins A and B, regressing KA showed significantly more regional tumor labeling (88%/88% vs. 57%/33%, p = 0.03) and a lower mean level of immunoreactivity (5%/4% vs. 19%/12%, p = 0.001) compared to mature KAs. These findings indicate a role for mitotic cyclins in the evolution of both SCC and KA. The overlapping patterns of expression for these mitosis-related antigens suggest that KAs represent a variant of SCC that exhibit an overwhelming but not absolute tendency to involute.
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Tran TA, DuPree M, Carlson JA. Neutrophilic lobular (pustular) panniculitis associated with rheumatoid arthritis: a case report and review of the literature. Am J Dermatopathol 1999; 21:247-52. [PMID: 10380046 DOI: 10.1097/00000372-199906000-00007] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Rheumatoid nodules, which affect the subcutis around joints, are the most frequent specific cutaneous lesions of rheumatoid arthritis (RA). Panniculitis is a rarely reported and nonspecific complication of RA. We report a 42-year-old woman with seropositive RA who presented with a 2-month history of lower leg panniculitis. Biopsy of a leg nodule showed a lobular neutrophilic infiltrate with lipophages and central basophilic necrosis. In addition, focal changes of lipomembranous fat necrosis indicative of ischemic damage were identified at the margins of the lobular infiltrate. Neutrophilic lobular panniculitis is commonly detected in panniculitis secondary to bacterial infections, pancreatitis, and factitial causes. However, this pattern of panniculitis has also been reported in some cases of erythema nodosum-like lesions found in Behçet disease or bowel bypass syndrome and in rare cases of seropositive RA. These reported histologic findings fall into the spectrum of neutrophilic vascular reactions described by Jorizzo and Daniels for RA-associated dermatoses. In view of these findings. RA and related neutrophilic dermatoses (e.g., Behçet disease) should be included in the differential diagnosis of neutrophilic lobular panniculitis.
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Mattern RH, Tran TA, Goodman M. Conformational analyses of cyclic hexapeptide analogs of somatostatin containing arylalkyl peptoid and naphthylalanine residues. J Pept Sci 1999; 5:161-75. [PMID: 10323196 DOI: 10.1002/(sici)1099-1387(199904)5:4<161::aid-psc177>3.0.co;2-f] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We report the conformational analysis by 1H-NMR in DMSO and computer simulations involving distance geometry and molecular dynamics simulations of peptoid analogs of the cyclic hexapeptide c-[Phe11-Pro6-Phe7-D-Trp8-Lys9-Thr10] L-363,301 (the numbering refers to the positions in native somatostatin). The compounds c-[Phe11-Nphe6-Nal7-D-Trp8-Lys9-Thr10] (Nphe6-Nal7 analog 1), c-[Nal11-Nphe6-Phe7-D-Trp8-Lys9-Thr10] (Nal11-Nphe6 analog 2) and c-[Phe11-Nnal6-Phe7-D-Trp8-Lys9-Thr10] (Nnal6 analog 3), where Nphe denotes N-benzylglycine and Nnal denotes N-(1-naphthylmethyl)glycine, are subjected to SAR studies in order to investigate the influence of the bulky naphthyl aromatic ring on the conformation. The Nal11-Nphe6 and Nphe6-Nal7 analogs exhibit potent binding to the hsst2, hsst3 and hsst5 receptors, whereas the Nnal6 analog has decreased binding affinity to all receptors but is more selective towards the hsst2 than the other two analogs and L-363,301. The conformational search employing distance geometry, energy minimization and molecular dynamic simulations gives insight into the conformational flexibility of these analogs. The molecules adopt both cis and trans orientations of the peptide bond between residues 11 and 6. The cis isomers of these analogs adopt type II' beta-turns with D-Trp in the i + 1 position and type VIalpha beta-turns with the cis peptide bond between residues 6 and 11. The results of free and distance restrained molecular dynamics simulations at 300 K indicate that the Nphe6-Nal7 and Nal11-Nphe6 compounds adopt a preferred backbone conformation which can be described as 'folded' about residues 7 and 10. The Nnal6 analog, which binds less effectively to the hsst receptors, has a more flexible backbone structure than the Nal11-Nphe6 and Nphe6-Nal7 analogs and prefers a 'flat' structure with regard to the orientations about Phe7 and Thr10 during molecular dynamics simulations.
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Tran TA, Mattern RH, Morgan BA, Taylor JE, Goodman M. Synthesis and binding properties of cyclohexapeptide somatostatin analogs containing naphthylalanine and arylalkyl peptoid residues. J Pept Sci 1999; 5:113-30. [PMID: 10323556 DOI: 10.1002/(sici)1099-1387(199903)5:3<113::aid-psc176>3.0.co;2-n] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We report the synthesis, binding affinities to the recombinant human somatostatin receptors, and structure-activity relationship studies of compounds related to the cyclic hexapeptide, c-[Pro6-Phe7-D-Trp8Lys9-Thr10-Phe11], L-363,301 (the numbering in the sequence refers to the position of the residues in native somatostatin). The Pro residue in this compound is replaced with the arylalkyl peptoid residues Nphe (N-benzylglycine), (S)betaMeNphe [(S)-N-[alpha(-methyl)benzyl]glycine] or (R)betaMeNphe [(R)-N-[(alpha-methyl)benzyl]glycine] and L-1-naphthylalanine is incorporated into either position 7 or 11 of the parent compound. The synthesis and binding data of the Nnal6 ([N-naphthylmethyl]glycine) analog of L-363,301 is also reported. The incorporation of the Nnal residue into position 6 of L-363,301 resulted in an analog with weaker binding affinities to all hsst receptors but enhanced selectivity towards the hsst2 receptor compared with the parent compound. The other compounds bind effectively to the hsst2 receptor but show some variations in the binding to the hsst3 and hsst5 receptors resulting in different ratios of binding affinities to the hsst5 and hsst2 or hsst3 and hsst2, respectively. The incorporation of the Nphe residue into position 6 and the Nal residue into position 7 of L-363,301 led to a compound which binds potently to the hsst2 and has increased selectivity towards this receptor (weaker binding to hsst3 and hsst5 receptors) compared with the parent compound. The analogs with beta-methyl chiral substitutions in the aromatic peptoid side chain and Nal in position 7 or 11 bind effectively to the hsst2 and hsst5 receptors. They exhibit similar ratios of binding affinities to the hsst5 and hsst2 receptors as observed for L-363,301. There are however minor differences in binding to the hsst3 receptor among these analogs. These studies allow us to investigate the influence of additional hydrophobic groups on the binding activity to the isolated human somatostatin receptors and the results are important for the design of other somatostatin analogs.
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Mu XC, Tran TA, Dupree M, Carlson JA. Acquired vulvar lymphangioma mimicking genital warts. A case report and review of the literature. J Cutan Pathol 1999; 26:150-4. [PMID: 10235381 DOI: 10.1111/j.1600-0560.1999.tb01820.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A 44-year-old female developed confluent, dusky red, pruritic labial papules clinically suspected to be genital warts. She had a long-standing history of Crohn's disease with vulvar fistulae. The papular eruption developed after several bouts of cellulitis in a region of vulvar lymphedema. Shave biopsy of a papule exhibited papillated epidermal hyperplasia overlying a dermis with a 'Swiss-cheese' appearance secondary to lymphedema and superficial ectatic thin-walled vascular spaces characteristic of lymphangiectasias. Review of published cases reveals that acquired lymphangiomas often affect the vulva compared to other cutaneous sites and can be associated with surgery, radiation therapy, infection (e.g., erysipelas, tuberculosis), Crohn's disease, congenital dysplastic angiopathy and congenital lymphedema. Rather than translucent vesicles ('frog spawn') typical of extragenital cutaneous lymphangiomas, vulvar lymphangiomas often present as verrucous papules that can be mistaken for genital warts. In this case, we believe that the combination of vulvar Crohn's disease and recurrent cellulitis resulted in local lymphatic destruction, lymphedema and ultimately symptomatic lymphangiectasias that mimicked genital warts.
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Tran TA, Mattern RH, Morgan BA, Taylor JE, Goodman M. Synthesis and binding potencies of cyclic hexapeptide analogs of somatostatin incorporating acidic and basic peptoid residues. THE JOURNAL OF PEPTIDE RESEARCH : OFFICIAL JOURNAL OF THE AMERICAN PEPTIDE SOCIETY 1999; 53:134-45. [PMID: 10195451 DOI: 10.1034/j.1399-3011.1999.00002.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The synthesis, binding affinity, and structure-activity relationships of compounds related to the cyclic hexapeptide, c[Pro6-Phe7-D-Trp8-Lys9-Thr10-Phe11], L-363,301 (the numbering in the sequence refers to the position of the residue in native somatostatin) is reported. The Pro residue in this compound is replaced with the peptoid residues Nasp [N-(2-carboxyethyl) glycine], Ndab [N-(2-aminoethyl) glycine] and Nlys [N-(4-aminobutyl) glycine]. This series of compounds enables us to draw conclusions about the influence of positively or negatively charged residues in the bridging region on the binding affinity towards the isolated human somatostatin receptors. A loss of binding to the recombinant human somatostatin (hsst) receptors in the Nasp analog compared with L-363,301 and compared with the Ndab and Nlys analogs clearly demonstrates that the presence of an acidic residue in the bridging region is unfavorable for binding to the hsst receptors. Comparison between the Ndab analog and the Nlys analog suggests that the presence of a basic residue in the bridging region might be advantageous for binding to the hsst5 receptor provided that the residue bearing the basic group extends far enough to allow for interaction with the receptor, while the length of the basic peptoid residue does not influence binding to the hsst2 receptor. These results are useful for the design of hsst5 selective somatostatin analogs.
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Mattern RH, Tran TA, Goodman M. Conformational analyses by 1H NMR and computer simulations of cyclic hexapeptides related to somatostatin containing acidic and basic peptoid residues. THE JOURNAL OF PEPTIDE RESEARCH : OFFICIAL JOURNAL OF THE AMERICAN PEPTIDE SOCIETY 1999; 53:146-60. [PMID: 10195452 DOI: 10.1034/j.1399-3011.1999.00003.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We report the conformational analysis by 1H NMR in DMSO and computer simulations involving distance geometry and molecular dynamics simulations at 300K of peptoid analogs of the cyclic hexapeptide c-[Phe11-Pro6-Phe7-D-Trp8-Lys9-Thr10]. The analogs c-[Phe11-Nasp6-Phe7-D-Trp8-Lys9-Thr10](1), c-[Phe11-Ndab6Phe7-D-Trp8-Lys9-Thr10] (2) and c-[Phen11-Nlys6-Phe7-D-Trp8-Lys9-Thr10](3) where Nasp denotes N-(2-carboxyethyl) glycine, Ndab N-(2-aminoethyl) glycine and Nlys N-(4-aminobutyl) glycine are subject to conformational studies. The results of free and restrained molecular dynamics simulations at 300K are reported and give insight into the conformational behaviour of these analogs. The compounds show two sets of nuclear magnetic resonance signals corresponding to the cis and trans orientations of the peptide bond between residues 11 and 6. The backbone conformation of the cis isomers that we believe are the bioactive isomers of the three compounds are very similar to each other while there are larger variations amongst the trans isomers. The binding data to the isolated receptors show that the introduction of the Nlys residue in analog 3 leads to an enhancement of binding potency to the hsst5 receptor compared with analog 2 while maintaining identical binding potency to the hsst2 receptor. The Nasp6 analog 1 binds weakly to the hsst2 and is essentially inactive towards the other receptors. Comparison of the conformations and binding activities of these three analogs indicates that the Nlys residue extends sufficiently far to allow binding to a negatively charged binding domain on the hsst5 receptor. According to this model, the Ndab analog 2 cannot extend far enough to allow for binding to the receptor pocket. The loss of activity observed for the Nasp6 compound 1 indicates that the presence of a negatively charged residue in position 6 is unfavorable for binding to the hsst receptors.
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Wiley MJ, Tran TA. Perioperative urinary catheterisation in conjunction with epidural anaesthesia for hip and knee arthroplasty. Is it safe? INTERNATIONAL JOURNAL OF SURGICAL INVESTIGATION 1999; 1:157-60. [PMID: 11341636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
The place of indwelling urinary catheterisation following epidural anaesthesia to prevent acute retention of urine after hip and knee arthroplasty is controversial. Even with the use of aseptic techniques and closed sterile drainage, bacteriuria has been reported in 10-27% of catheterised patients. A prospective trial was carried out in 68 consecutive patients undergoing knee or hip joint arthroplasty with epidural anaesthesia to investigate the perioperative complications of short term urinary catheterisation. Following establishment of combined epidural and general anaesthesia, all patients underwent urinary catheterisation under aseptic technique by a member of the surgical team. Prophylactic antibiotics were given prior to insertion and continued for 24-48h postoperatively to minimise the risk of prosthetic infection. The mean indwelling urinary catheter (IDC) period was 3.6 days (range 2-14). There were three (4.4%) urinary tract infections (UTIs) all of which resolved with appropriate antibiotics. Two were detected upon removal of the urinary catheter and one was detected on the seventh postoperative day when symptoms were detected. No patient required recatheterisation. There was no other infective morbidity or wound infection. Our findings suggest the use of IDC for short periods combined with prophylactic antibiotics is safe in the perioperative phase of joint arthroplasty.
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Sizun J, Tran TA, Lazartigues A. [Can we improve the neuro-intellectual and behavioral prognosis of premature infants by modifying their environment?]. Arch Pediatr 1999; 6:7-11. [PMID: 9974088 DOI: 10.1016/s0929-693x(99)80065-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Abstract
Recent evidence has implicated cyclins and cyclin-dependent kinases in the evolution and progression of various malignancies. We studied the immunohistochemical expression of cyclin A, cyclin B, and cyclin-dependent kinase p34cdc2 in a broad spectrum of benign and malignant melanocytic lesions. Formalin-embedded, parrafin-fixed tissue sections from 66 malignant melanomas (MM) and 60 benign nevi were examined for the expression of these cell-cycle proteins. The results were compared with the standard proliferative marker Ki-67 and mitotic index. MM showed significantly higher immunoreactivity for cyclin A, cyclin B, p34cdc2, and Ki-67 compared with benign nevi. Cyclin A, p34cdc2, and Ki-67 displayed strong co-expression in MM. Overexpression of cyclin A and p34cdc2 correlated with histological type, mitotic activity, Ki-67 index, tumor thickness, Clark's level, and clinical outcome in MM. In invasive MM, increased immunostaining of cyclin A and Ki-67 were associated with decreased patient survival. These findings indicate potential roles of mitotic cyclins and cyclin-dependent kinases in the pathogenesis and progression of malignant melanoma.
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Tran TA, Mattern RH, Afargan M, Amitay O, Ziv O, Morgan BA, Taylor JE, Hoyer D, Goodman M. Design, synthesis, and biological activities of potent and selective somatostatin analogues incorporating novel peptoid residues. J Med Chem 1998; 41:2679-85. [PMID: 9667958 DOI: 10.1021/jm970393l] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We report the synthesis, bioactivity, and structure-activity relationship studies of compounds related to the Merck cyclic hexapeptide c[Pro6-Phe7-d-Trp8-Lys9-Thr10-Phe11], L-363,301 (the numbering in the sequence refers to the position of the residues in native somatostatin). The Pro residue in this compound is replaced with arylalkyl peptoid residues. We present a novel approach utilizing beta-methyl chiral substitutions to constrain the peptoid side-chain conformation. Our studies led to molecules which show potent binding and increased selectivity to the hsst2 receptor (weaker binding to the hsst3 and hsst5 receptors compared to L-363, 301). In vivo, these peptoid analogues selectively inhibit the release of growth hormone but have no effect on the inhibition of insulin. The biological assays which include binding to five recombinant human somatostatin receptors carried out in two independent laboratories and in vivo inhibition of growth hormone and insulin provide insight into the relationship between structure and biological activity of somatostatin analogues. Our results have important implications for the study of other peptide hormones and neurotransmitters.
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Mattern RH, Tran TA, Goodman M. Conformational analyses of somatostatin-related cyclic hexapeptides containing peptoid residues. J Med Chem 1998; 41:2686-92. [PMID: 9667959 DOI: 10.1021/jm970392t] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We report the conformational analysis by 1H NMR in DMSO and computer simulations involving distance geometry and molecular dynamics simulations of a series of peptoid analogues of the cyclic hexapeptide c[Phe11-Pro6-Phe7-d-Trp8-Lys9-Thr10] (1). The proline residue in compound 1 is replaced with the peptoid residues N-benzylglycine (Nphe) (compound 2), N-(S)-alpha-methylbenzylglycine [(S)-beta-MeNphe] (compound 3), and N-(R)-alpha-methylbenzylglycine [(R)-beta-MeNphe] (compound 4). The peptoid analogues 2 and 4 exhibit potent binding activities to the hsst2 receptor, while the binding affinities to the hsst5 and to the hsst3 receptors are reduced compared to that of the parent compound 1. Compound 3 shows reduced binding activities to the hsst2, hsst3, and hsst5 receptors compared to compound 1. The results of in vivo assays indicate that these compounds inhibit the growth hormone release but do not affect the insulin release. These peptoid-containing analogues show two sets of NMR signals corresponding to cis and trans conformations of the peptide bond between Phe11 and Nxaa6. We demonstrate that the backbone conformation and the orientation of the relevant side chains of compound 1 are maintained in the cis isomers of the peptoid analogues which adopt a type VI beta-turn centered around residues 11 and 6 and a type II' beta-turn with d-Trp in the i+1 position. The enhanced selectivity of the peptoid-containing analogues compared to compound 1 and the results of the conformational analysis suggest that the presence of a conformationally constrained hydrophobic group in position 6 in complementary topology to the Phe11 side chain enhances selective binding to the hsst2 receptor.
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Tran TA, Kallakury BV, Ambros RA, Ross JS. Prognostic significance of tumor necrosis factors and their receptors in nonsmall cell lung carcinoma. Cancer 1998; 83:276-82. [PMID: 9669810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND In vitro studies have shown an antiproliferative effect of tumor necrosis factor (TNF) against various nonsmall cell lung carcinoma (NSCLC) cell lines. However, clinical trials of combined interleukin-2 and TNF-alpha in patients with advanced NSCLC have demonstrated both conflicting and disappointing results. METHODS Immunohistochemical (IHC) staining was performed on formalin fixed, paraffin embedded tissues from 39 bronchogenic adenocarcinomas and 32 squamous cell carcinomas using polyclonal antibodies against TNF-alpha, TNF-beta, TNF-R1, and TNF-R2 proteins. IHC positivity was correlated with tumor stage, grade, and patient survival. RESULTS Significant coexpression of TNF-alpha, TNF-beta, TNF-R1, and TNF-R2 was observed in NSCLC (significance range, P < 0.001-0.02). Although immunoreactivity for TNFs remained high in all tumor stages, a loss of TNF-R expression was found in advanced NSCLC (P < 0.006 for TNF-R1 and P < 0.003 for TNF-R2), suggesting down-regulation of TNF-Rs in the process of tumor progression. When all stages were considered together, immunoreactivity for TNF-beta(P < 0.001), TNF-R1, and TNF-R2 (both P < 0.001) significantly correlated with favorable outcome in univariate analysis. However, when stages were studied separately, an association between immunopositivity for TNF-Rs and favorable prognosis was found only in NSCLC without distant metastasis (P < 0.04 and P < 0.005 for TNF-R1 and TNF-R2 in Stage I [according to the American Joint Committee on Cancer staging system] disease, and P < 0.03 and P < 0.02 for TNF-R1 and TNF-R2 in Stage III disease). On multivariate analysis, increased expression of TNF-R1 (P < 0.003) and TNF-R2 (P < 0.001) as well as tumor stage (P < 0.001) independently predicted favorable outcome in patients with NSCLC. CONCLUSIONS Although NSCLC exhibits strong coexpression of TNF-alpha, TNF-beta, TNF-R1, and TNF-R2, there is a loss/down-regulation of TNF receptors in high stage tumors. TNF-R1 and TNF-R2 positivity independently predicts favorable outcome in NSCLC, particularly in tumors with no clinically distant metastasis. The current study supports a role for TNFs and their receptors in the evolution and progression of NSCLC.
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Tran TA, Carlson JA, Basaca PC, Mihm MC. Cellular blue nevus with atypia (atypical cellular blue nevus): a clinicopathologic study of nine cases. J Cutan Pathol 1998; 25:252-8. [PMID: 9696290 DOI: 10.1111/j.1600-0560.1998.tb01729.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Atypical cellular blue nevus (ACBN) has clinicopathologic features intermediate between typical cellular blue nevus (CBN) and the rare malignant blue nevus (MBN)/malignant melanoma (MM) arising in a CBN. Herein we report 9 cases of ACBN. The patients were caucasian (6 females and 3 males) with a mean and median age of 47/51 years. Two patients complained of recent changes and about half of these tumors were located on the buttocks or scalp, averaging 1.5 cm in diameter. Histologically, they were characterized by architectural atypia (infiltrative margin and/or asymmetry) and/or cytologic atypia (hypercellularity, nuclear pleomorphism, hyperchromasia, mitotic figures, and/or necrosis). Assessment of the expression of 3 tissue markers demonstrated rare solitary cell staining with oncogene product bcl-2, and a proliferative index of 23+/-19 and 39+/-30 cells/10 high power field with antibodies to PCNA and Mib-1, respectively. No significant differences were detected comparing the above levels of expression to a control group of 15 CBN; however, ACBNs tended to show a higher proliferative index by PCNA and Mib-1 as well as a significantly higher mitotic rate (1/10 HPF vs. 0; p=0.001). Analysis of DNA content showed DNA aneuploidy in both groups. Follow-up data on 9 of 9 patients showed 1 patient dead without disease and 8 alive without disease (mean/median follow-up 42/32 months, range 15-96 months). No patient during this follow-up time has experienced either a local recurrence or lymph node or visceral metastasis. These findings highlight the close resemblance of ACBN to the natural history of CBN. Nevertheless, many of the distinguishing histologic features of ACBN are also those of MBN. Because of these intermediate clinicopathologic features, ACBN warrant close scrutiny and long-term follow-up.
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Tran TA, Jennings TA, Ross JS, Nazeer T. Pseudomyxoma ovariilike posttherapeutic alteration in prostatic adenocarcinoma: a distinctive pattern in patients receiving neoadjuvant androgen ablation therapy. Am J Surg Pathol 1998; 22:347-54. [PMID: 9500777 DOI: 10.1097/00000478-199803000-00010] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Neoadjuvant combination endocrine therapy that uses leuprolide and flutamide may result in various histologic changes in nontumoral and cancerous prostatic tissues. Posttreatment pseudomyxoma ovariilike change in prostatic adenocarcinoma is a distinctive alteration that may be the only evidence of regressed tumor and can be potentially confused with mucinous carcinoma. We studied 53 clinically localized prostatic adenocarcinomas after 3 to 5 months of treatment with leuprolide and flutamide. Alterations in prostatic adenocarcinoma in posttreatment radical prostatectomy specimens were assessed and compared with pretreatment needle biopsies. All radical prostatectomy specimens exhibited previously well-characterized therapy-associated changes in benign and malignant elements. Thirteen (20%) cases exhibited a distinctive alteration not seen in pretreatment needle biopsies that consisted of minute to large pools of extravasated secretions that resembled pseudomyxoma ovarii and that dissected through prostatic stroma with an infiltrative appearance when viewed at low power. Associated recognizable tumor was present in 10 of 13 (77%) of these cases. Secretions were basophilic in routine sections and contained occasional degenerated cells. Rare pancytokeratin positive cells were seen at the secretion/stroma interface with uniformly negative staining for the high molecular weight keratin 34 beta E-12. The secretions were periodic acid-Schiff positive after diastase digestion and were mucicarminophilic and reactive with Alcian blue at a pH of 2.5. These foci comprised < 5% of the tumor in 5 cases and 5-40% in 5 cases. In 3 cases, 1-2 foci < 1.0 mm exhibited the pseudomyxoma ovariilike changes and were the only evidence of treated tumor. There was no correlation between the presence of pseudomyxomalike change and dose/duration of neoadjuvant therapy, postprostatectomy clinical follow-up, original or final Gleason pattern/score, or pathologic stage. Pseudomyxoma ovariilike change consists of extravasated acid mucin, lacks prostatic basal cells, often occurs in intimate association with residual prostatic adenocarcinoma in posttreatment radical prostatectomy specimens, and probably represents tumor regression as a result of tumor cell attrition secondary to androgen ablation.
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Tran TA, Kallakury BV, Carter J, Wolf BC, Ross JS. Coexistence of granular cell tumor and ipsilateral infiltrating ductal carcinoma of the breast. South Med J 1997; 90:1149-51. [PMID: 9386062 DOI: 10.1097/00007611-199711000-00020] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Granular cell tumor is a benign neoplasm that is rarely seen in the breast and can mimic carcinoma, both clinically and by gross pathologic examination. The coexistence of a granular cell tumor with a primary mammary carcinoma can potentially pose diagnostic and therapeutic problems. In this report, we document a granular cell tumor of the breast coexisting with an ipsilateral infiltrating ductal carcinoma in a 74-year-old woman and discuss its clinical significance.
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MESH Headings
- Aged
- Breast Neoplasms/pathology
- Breast Neoplasms/surgery
- Carcinoma, Ductal, Breast/pathology
- Carcinoma, Ductal, Breast/secondary
- Carcinoma, Ductal, Breast/surgery
- Diagnosis, Differential
- Female
- Granular Cell Tumor/pathology
- Granular Cell Tumor/surgery
- Humans
- Keratins/analysis
- Lymphatic Metastasis
- Mastectomy, Modified Radical
- Mastectomy, Segmental
- Neoplasms, Multiple Primary/pathology
- Phosphopyruvate Hydratase/analysis
- S100 Proteins/analysis
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Tran TA, Spencer SS, Javidan M, Pacia S, Marks D, Spencer DD. Significance of spikes recorded on intraoperative electrocorticography in patients with brain tumor and epilepsy. Epilepsia 1997; 38:1132-9. [PMID: 9579960 DOI: 10.1111/j.1528-1157.1997.tb01203.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE Patients with medically intractable epilepsy due to brain tumors may undergo resective surgery for treatment of both the tumor and the epilepsy. In this instance, the extent of surgical resection is sometimes guided by spikes recorded on intraoperative electrocorticography (ECoG). Whether spikes recorded by electrocorticography imply active epileptogenicity has not been addressed adequately. METHODS We performed preresection and postresection electrocorticography on 36 patients with brain tumor and seizures. There were 31 low-grade gliomas, 4 high grade gliomas, and 1 dysembryonic neuroepithelial tumor. Patients had resection of the tumor to normal tissue margins only. No additional surgery was performed, based on electrocorticography findings. Patients were divided into 2 groups: Group I (no seizures or rare seizures after resection) and Group II (recurrent seizures). Recorded spikes were analyzed for spike distribution and spike discharge rate. RESULTS On preresection ECoG, 85% of patients in Group I and 88% of patients in Group II had spikes. In Group I, 70% of patients had spikes over the tumor bed, and 63% of patients had spikes in the surrounding tissue. In Group II, 55% of patients had spikes over the tumor bed and 89% of patients had spikes in the surrounding tissue. Spike distribution and discharge rate did not correlate with outcome. On postresection ECoG, 60% of patients in Group I and 67% of patients in Group II had residual spikes. In Group I, 46% of patients had spikes along the margin of resection and 26% of patients had extramarginal spikes. In Group II, 50% had spikes along the margin of resection and 67% of patients had extramarginal spikes. CONCLUSIONS The difference in spike distribution in the extramarginal area between the 2 groups was not statistically significant, but showed a trend toward a relationship between postresection spikes and seizure recurrence.
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Wu TK, Wu AS, Tran TA, Lee CY. Neuronal intestinal dysplasia presenting as an abdominal mass: report of a case. Dis Colon Rectum 1997; 40:862-5. [PMID: 9221867 DOI: 10.1007/bf02055447] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
An unusual clinical presentation of a patient with neuronal intestinal dysplasia is presented. A 46-year-old male noted a palpable mass in the right lower quadrant of his abdomen for two months. A computed axial tomographic scan showed a thickened wall of the cecum with a tumor-like appearance. The excised specimen consisted of a mass caused by the thickened, edematous wall of the dilated cecum and appendix. The wall of the cecum and appendix measured up to 2.5 and 0.8 cm, respectively, in thickness. Microscopic studies showed extensive hyperplasia and hypertrophy of the ganglia and nerve plexuses and hypertrophy of the muscularis propria, consistent with neuronal intestinal dysplasia.
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Tran TA, Kallakury BV, Sheehan CE, Ross JS. Expression of CD44 standard form and variant isoforms in non-small cell lung carcinomas. Hum Pathol 1997; 28:809-14. [PMID: 9224749 DOI: 10.1016/s0046-8177(97)90154-4] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
CD44, a cell adhesion molecule, has been implicated in tumor invasion and metastasis in certain malignancies. We studied the expression of CD44 standard (CD44s) and variant isoforms (CD44v) in 98 non-small cell lung carcinomas (NSCLCs) by immunohistochemistry and correlated the observations with clinical outcome. Formalin-fixed, paraffin-embedded archival tissues from 49 squamous cell carcinomas (SCCs) and 49 adenocarcinomas (ACs) were immunostained after microwave irradiation with monoclonal antibodies against CD44s and CD44v3, v4/5, v6, v7/8, and v10, and the results were correlated with histological tumor type, tumor stage, recurrence, and survival rates. SCCs of the lung showed strong membranous expression of each of the CD44s, v3, v4/5, v6, and v10 proteins in comparison with ACs (P < .0001). Staining for CD44 v4/5 was overwhelmingly positive in SCCs (72%) as compared with ACs (2.2%). Intense immunoreactivity for CD44v6 was present in 19 of 20 (95%) metastatic lung carcinomas. The bronchiolar basal cells and alveolar pneumocytes were positive for CD44s, v3, and v6. CD44s and variant isoform expression did not correlate with tumor stage, recurrence, and survival rates. In conclusion, there is significant immunopositivity of CD44s and variant isoforms in SCCs over ACs of the lung. Expression of CD44v6 may suggest an increased risk for local lymph node metastasis in NSCLCs. CD44v4/5 reactivity may be useful to discriminate squamoid differentiation in poorly differentiated NSCLCs.
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Wagner AK, Ehrenberg BL, Tran TA, Bungay KM, Cynn DJ, Rogers WH. Patient-based health status measurement in clinical practice: a study of its impact on epilepsy patients' care. Qual Life Res 1997; 6:329-41. [PMID: 9248315 DOI: 10.1023/a:1018479209369] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The objective was to assess the potential benefits of the routine use of the MOS SF-36 Health Survey (SF-36) in the care of ambulatory patients. The design was a longitudinal, prospective, randomized, controlled study set in the outpatient neurology clinic at the New England Medical Center. There were 163 consecutive patients with epilepsy who had 210 follow-up visits with one of two epileptologists. The patients completed the SF-36 before the patient-physician encounter and the forms were optically scanned. The SF-36 results of the intervention group patients were given to the physicians before the encounter and withheld for control group patients. For intervention group patients, the physicians completed a questionnaire assessing the impact of the SF-36 on the process of care. After the visit, all patients completed a satisfaction questionnaire. The main outcome measures were the physicians' responses to standardized questions about the usefulness of the SF-36 for communication with and management of epilepsy patients and the patients' responses to standardized questions about their satisfaction with care. The physicians indicated that the SF-36 provided new information in 63% of the intervention group encounters. A change in therapy was prompted in 13%. The physicians rated the SF-36 as at least moderately useful for communication in 14% of the encounters and to management in 8%. The lower (indicating worse health status) the patients' SF-36 scale scores, the more useful the SF-36 results were rated by the physicians for communication and management. It was concluded that the routine use of health status measures may enhance patients' care.
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Romoff TT, Tran TA, Goodman M. Urethane-protected N-carboxyanhydrides (UNCAs) as unique reactants for the study of intrinsic racemization tendencies in peptide synthesis. THE JOURNAL OF PEPTIDE RESEARCH : OFFICIAL JOURNAL OF THE AMERICAN PEPTIDE SOCIETY 1997; 49:281-92. [PMID: 9176811 DOI: 10.1111/j.1399-3011.1997.tb01128.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We have established that urethane-protected N-carboxyanhydrides (UNCAs) are uniquely suited for the study of intrinsic racemization tendencies in peptide synthesis. The UNCA allows epimerization only by the direct enolization pathway (Proton abstraction from the alpha-carbon) and does not decompose upon epimerization. A protocol employing the quantitative separation and analysis of enantiomeric N-protected amino acid derivatives by chiral HPLC has been developed to measure the intrinsic rate of racemization of UNCAs under widely varying reaction conditions. The influence of the tertiary amine structure, UNCA side chain structure, and solvent were studied. The same protocol was employed to study the intrinsic rate of racemization of N-protected activated amino acid intermediates generated via 'onium-type' activating reagents. We have shown that the trends influencing the intrinsic rate of racemization of UNCAs are maintained under the conditions of in situ activations, and are consistent with the trends found in classical studies in the literature. The results are relevant to peptide synthesis both in solution and on solid phase. The intrinsic rate of racemization for any type of activation with any tertiary amine can be measured by this protocol.
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